Process of making sulfur trioxid.



nmvsms v I PATENTED 13m 20, 1904.

H. S.BLAGKMORE.

v PROCESS OF- MAKING SULFUR TRIO XID.

APPLICATION FILED MAY 11, 1901.

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PATENTBD DEG. 20, 1904.

H. s. BLAGKMORE. PROCESS OF MAKING SULFUR TRIOXID.

APPLICATION FILED MAY 11, 1901.

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\ \xxTr UNITED STATES Patented December QO, 1904.

PATENT OFFICE.

PROCESS OF MAK'INIYG'SULFUR TRIOXID.

SPECIFICATION forming part of Letters Patent N 0. 778,099, datedDecember'20, 1904.

To all whom it may concern.-

- Beitknown that I, HENRY SPnNonR BLACK- MORE, a citizen of the UnitedStates, residing at-206 South Ninth avenue, Mount Vernon, in the countyof l/Vestchester and State of New York, have invented certain new anduseful Improvements in Processes of Making Sulfur Trioxid; and I dohereby declare the following to be a full, clear, and exact descriptionof the invention, such as will enable others skilled in the art to whichit appertains to make and use the same. Y t

The object of'my invention is to produce compounds containing sulfur,such as sulfur trioxid, (SO3,) which evolve heat in their formation insuch a manner that the temperature is prevented from rising to a pointat which the compound desired is dissociated, whereby its continuousproduction is prohibited, and consists in simultaneously producingsubstances which absorb heat on their formation and the sulfur compounddesired, the ingredients being so apportioned, adjusted, and disposedthat the heat evolved during the formation of the sulfur compound isabstracted by the substance absorbing. heat during its production tosuch a degree that the temperature is prevented from reaching thedissociating-point of the compound desired. This abstraction orabsorbtion of heat by chemical means 1 term chemical refrigeration.

My invention relates specifically to certain new and novel features andsteps for perform- I ing a reaction between sulfur dioxid and gaseousoxidizing agents in the format1on ofsulfur trioXid, whereby atemperature suflicient to dissociate sulfur trioxid or preclude itsformation is prohibited by abstracting the heat evolved in the formationof the sulfur trioxid by a simultaneously-produced substance which 7absorbs heat on its formation, the ingredients being so apportioned anddisposed that the heat evolved by one is taken up by the other to such adegree as to practically prevent the accumulation of heat to aninjurious point. By properly apportioning the reacting ingredients theprocess of making sulfur trioxid may be carried on continuously, thereaction being induced by the direct applicaa transverse verticalApplication filed May 11,1901. Serial No. 59,814.

tion of controlled heat in preference to heat dislodged, generated, orproduced through the mediation of catalytic or condensation action offinely-divided metal or so-called contact substances, (Gcmots Physics)such as platinized asbestos, &c., on gases present,

. which soon become inoperative by absorption,

saturation of gases, or destructive action of injurious contaminationsand can only be regenerated by expensive chemical process to regaintheir activity.

In carrying out my invention for the production of sulfur trioXid Iproceed as follows, reference being had to the accompanying drawings,which illustrate a preferred form of apparatus which I employ for thepurpose.

'Referring to the drawings, Figure '1 is a vertical longitudinal sectionof myapparatus.

Fig. 2 is an enlarged vertical section showing the electric diaphragmsand the connections of the transforming-chamber. Fig. 3 is across-section of one of the rings of the electric connection of thetransforming-chamber and an electric gauze diaphragm connectedtherewith. Fig. 4 is a transverse section of a modified form ofapparatus, showing the transforming-compartments of elongated form andprovided with water-jackets. Fig.

i 5 is a vertical longitudinal section of the apparatus on the lines00m, Fig. 4; and Fig. 6 is section on the lines y y, Fig. 4:.

5 Similar letters refer to corresponding parts in the several views.

The letter -A designates a transformingchamber of cylindrical or otherform provided at its top with an elbow B and pipe C, the latterconnected with a jacketed condenser D in any desired air-tight manner.

The lower end of the transforming-chamber A is provided with adetachable head E, having a central stuffing-box or screw-threaded plugF, of insulating material, connected therewith and in which is fitted arod or electric connection .G, the upper portion of which is formed insection having screw-threaded connections, as shown at a a a in Fig. 2.

The transforming-chamber A, like the electric connection G, is partlycomposed'of sections, as shown at b 6 Z), (see Figs. 1 and 2,) ring tocorresponding parts in the several the said sections being joinedtogether by the threaded ends 0 0 c".

A series of metallic-gauze diaphragms (Z, preferably of gold-platedcopper, are arranged within the transforming-chamber A, the saiddiaphragms being securely held in relative positions by the abuttingshoulders of the screw-threaded ends of the transformingehamber ringsand of the central connection thereof. The upper and lower diaphragms cland d are arranged in several thicknesses, forming a heat-absorber andflash-preventer and insulated from the electric connection G, as shownat e e, for the purposes hereinafter fully described.

Peep-holes ff, having mica fronts or covers h h, are located at theopposite sides of the combustion or transforming compartment A to enablethe attendant to view the interior thereof and provide for regulatingthe apparatus as occasion may require.

The letters sand 2" and i designate electric wires which arerespectively connected with the electric conductor G and the walls ofthe transforming-chamber A by ordinary means.

The lower part of the transforming-chamber is provided horizontally witha pipe-section H, having a detachable end or head 7t", within which istightly fitted a tube Z, the latter provided with a T-head Z and aninletpipe m, while within the stem of the T-head and the tube Z isarranged a pipe n for the purposes hereinafter fully specified.

In constructing an apparatus for carrying out my invention on amanufacturing scale it is found advisable not to have the heating gauzediaphragms (Z d of a width greater than two inches from the centralconductor on account of the tendency of the same to sag, becomeoverheated, and fuse. I therefore prefer the form of apparatus as shownin Figs. 4, 5, and 6, wherein it is seen that thetransforming-compartments are of elongated form and the centralconductor instead of a rod consists of a strip of metal. This form oftransforming apparatus is adapted to carry a heated gauze diaphragm offrom three to four feet in length and four inches in width 0., twoinches on either side of the central conductor, which extends throughthe center of the transforming-compartment to within two inchesof eitherend, as shown in Fig. 4. In constructing a battery of this form ofapparatus it is advisable to separate the individual sections from eachother by means of a water-jacket z 2, which assists in maintaining thegases in a refrigerated condition, whereby the reaction is regulated bysupply of heat thereto by means ofheated gauze diaphragms. In all otherparticulars this preferred and modified form of apparatus is illustratedin Figs. 4, 5, and 6, in parts corresponding to Figs. 1, 2, and 3,except in form and construction, the same letters of referencereferviews.

In the operation of my invention for the production of sulfur trioxid Iintroduce the sulfur dioxid through the pipe m. and gradually introducea gaseous oxidizing compound, such as carbon dioxid, through the pipe11, allowing the two to enter in about equivalent proportions beforereaction, whereupon they become thoroughly mixed in the lower part oftransforming-chamber A. The mixed gases then pass up through theinsulated gauze flash-preventer (Z into the transforming-compartment A.A current of electricity is then passed through the connections 11 11 i,the same passing through the diaphragms (Z (Z, heating them inproportion to the strength of the current, either low or to whiteness,the tenn'ierature being somewhat gaged by the color of the diaphragm,which can be observed through the mica-closed peep-holesff". Asthemixture of sulfur dioxid and carbon dioxid comes in contact with theheated gauze diaphragms a reaction takes place, which may beillustn'uted by the following chemical formula or equation: SOa+GO2SOa-l-CO. It will be observed that the reaction which herc takes placeis of endothermic nature and that the oxidizingcompoundisreduced,producingaby-prodnet of endothermic or heat-absorbingcharacter-that is tosay, heat has to be supplied to the mixture tomaintain the reaction or oxidation and can only reach the point ofdissociation of the sulfur trioxid by the excessive application ofexternal heat.

In inducing the reaction between sulfur dioxid and a gaseous oxidizingcompound 1 heat the igniting gauze diaphragms (Z (Z to a bright red bypassing a current of electricity therethrough and then gradually passthe sulfur dioxid and gaseous oxidizing compound, such as carbon dioxid,through the same. As the mixture of sulfur dioxid and carbon dioxid passthrough the diaphragm (Z (l, heated to bright redness, a reaction takesplace, the carbon dioxid at that temperature assuming oxidizingproperties and gives up a portion of its oxygen to the gaseous sulfurdioxid, producing sublimed sulfur trioxid and carbonic oxid, whichproducts are rapidly conveyed from the heated sphere in juxtaposition tothe diaphragm by the current of flowing gas therethrough.

Care must be taken not to pass the mixture of carbon dioxid and sulfurdioxid through the diaphragm at a greater speed than will cool thediaphragm below a bright red heat, as the reduction of the carbon dioxidto tarbonic oxid and simultaneous oxidation of sulfur dioxid to sulfurtrioxid requires the addition of heat, for the reason that theby-productcarbonic oxid-absorbs a large portion of latent heat, whichheat had previously been liberated by oxidation to carbon dioxid.

It is well known that the oxidation of sulates heat in such quantity asto eventually accumulate to a temperature which prevents the formationof sulfur trioxid unless the sensible heat is mechanically abstracted.By my process the liberation of sensible heat in the oxidation of sulfurdioxid is entirely prevented, so that the sulphur dioxid becomesoxidized by what is termed an endothermic reaction@'. a, heat isabsorbed during the reaction instead of being liberated and mustnaturally be supplied thereto to maintain it. The reason for this factis that duringv the combination of carbon and oxygen in theproduction ofcarbon dioxid more sensible heat is liberated thanis liberated by theunion of oxygen and sulfur dioxid. Therefore by oxidizing sulfur dioxidwith this gaseous oxidizing agent the heat byunion of which has beendisengaged must be added to perform and maintain the reaction oroxidation of the sulfur dioxid therewith, and consequently thetemperature cannot rise to the dissociating-point of sulfur trioxidunless the heat is supplied in excessive quantities from anexterior'source. It will be observed that the heated sphere injuxtaposition to the diaphragm is maintained at a bright red, at whichtemperature carbon dioxid acts as an oxidizing agent. through arerapidly conveyed outside of the sphere at which the heat is supplied-2'.0., in juxtaposition to the diaphragmso that decompositionby'by-products is thus prevented thereafter.

The proportion of gases in case sulfur dioxid and carbon dioxid'areemployed is pref.- erably in volume of two parts of carbon dioxid toonepart of sulfur dioxid, the object beingto have an excess of carbondioxid, the

presence of which prevents the reduction of sulfur trioxid by thecarbonic oxid by-product as the gases cool after reaction. After thesulfur trioxid and carbonic oxid are thus pro-- duced by, means ofendothermic reaction they are conveyed through the water-jacketedcondenser D, where the sulfur-trioxid sublimate is condensed, and thecarbonic oxid, with excess of carbon dioxid, conducted therefrom, thecarbonic oxid oxidized by-burning to carbon dioxid and employed again asbefore.- The carbonic oxid in this process merely acts as a carrier ofoxygen, whereby the oxidation of sulfur dioxid is performed Withoutliberation. of sensible heat.

The current of gases introduced passing rapidly through the apparatuscarries the principal product of reaction,-z'. a, sulfur trioxid.quicklythrough and away from the heated gauze diaphragms, and at the same timeit is cooled by the surrounding body of gases andthen passes through theflash-pre-- venter cl, which consists of a number of layers of gauzeinsulated, as before described, from the central conductor, and thusalso acts The products passing there-' as a strainer or absorbent of anyexcess of finally condensed in the jacketed condenser D,

from which it may be removed from time to time, as desired, while thecarbonic oxid or other reduced oxidizing gaseous medium may bereoxidized and employed in future opera- 'tions.

It will be observed that the transformingcompartment A, in which theelectricallyheated diaphragms are located, is protected at the inlet andoutlet portions with heavy insu. lated gauze sections which prevent theignited mixture of gases in said compartment from conveying the flash oroxidizing reaction outside of the compartment and admits of controllingthe temperature and the product by the rapidity of the admission ofgases thereto during transformation. The electric diaphragms (Z (Z beingmaintained at a uniform temperature by carefully regulating thetemperature of the electric diaphragms d d in conformity with therapidity of flow of gases introduced, the production of sulfur trioxidmay be carried on continuously without interruption. 4

It is obvious that I can introduce any other compound gaseous oxidizingagent with the carbon dioxid, such as nitrogen I oxid, &c., mixed withsulfur dioxid and inducing a reaction between the same, by continuouslysupplying heat thereto in such proportion as to maintain the reaction oroxidation of the sulfur dioxid, but not to such a degree as to elevatethe temperature to the dissociatingpoint of sulfur trioxid, at whichtime the oxidation of sulfur dioxid would be precluded.

It can be readily seen that the heated diaphragms (Z d in thetransforming-compartment A serve to supply the heat wherebya reaction isinduced between the sulfur dioxid and the gaseous oxidizing compound asit comes in contact therewith, and the excess of heat absorbed therefromby the passing gases or products of reaction is primarily removed orabsorbed by the rapid-flowing gases admitted and the heat-absorbingdiaphragm cl.

It is obvious that by my process the oxidation of sulfur dioxid producedby reaction between sulfur dioxid and a gaseous oxidizing compound isinduced and maintained by a positive and controlled meansviz. theelectrically heated, gauze diaphragm throughwhich the mixture ofgases-have to pass-- and therefore is not subject to the difficultiesfound or met with in employing catalytic or contact substances, whichsoon become inoperative by absorption or saturation of gases and canonlybe reused by expensive process. of separation and regeneration.

The products of reaction in the case of the employment 'of carbon dioxidas an oxidizing agent with sulfur dioxid are sulfur trioxidand carbonicoxid, whlch products are conveyed through the condenser D, where thesulfur trioxid condenses in crystalline form and the by-productviz.,carbonic oxidre conducted to a reservoir from which it can be againemployed from time to time by oxidizing the same, mixing it with moresulfur dioxid, and conveying the mixture through the apparatus and thetransforming-compartment A, whereby the process may be carried on in acontinuous and uninterrupted manner.

I do not desire to confine myself to any particular gaseous oxidizingcompound, but have found nitrogen-oxid and carbon-dioxid mixture to bethe most efficient, the principal object being to oxidize sulfur dioxidto sulfur trioxid by the action of a gaseous oxidizing compound, thereaction of which on the sulfur dioxid is of endothermic nature.

The term gaseous as employed herein with reference to oxidizing agentsfor transforming sulfur dioxid into sulfur trioxid is intended toinclude a vaporized oxidizing compound capable of producing sulfurtrioxid from sulfur dioxid as well as an oxidizing gas per 80.

The term by means other than catalysis as employed in this specificationand preamble to certain claims is intended to imply a means for inducingreaction between the ingredients by the direct action of heat suppliedthereto rather than heat dislodged, generated, or produced from thesurrounding gases by the catalytic or condensation action of so-calledcatalytic substances thereon or union induced by the condensationproduced thereby.

The term endothermic byproduct as employed herein designates the thermiccharacter of the by-product or residue of the process with relation tothe product produced and oxidizing agent employed. For example,in thecase described employing carbon dioxid (CO2) as oxidizing agent it iswell known that the by-product, carbonic oxid, (C0,) contains more heatunits than carbon dioxid, (C02,) because heat is given out on producingcarbon dioxid (CO2) from carbonic oxid (CO) by combination with oxygen.Therefore on deoxidizing or reducing carbon dioxid (CO2) to carbonicoxid (CO) the carbonic oxid must be endothermic or heat-absorbing withrelation to carbon dioxid.

It should be noted that as the sulfurous gas comes in contact with thegold-plated copper gauze it combines therewith, forming a coating ofgold-copper sulfid, which prevents further action on the metal parts andisolates the metal from further contact with the surrounding gases orfluids, but does not prevent the passage of heat therethrough for thepurpose of inducing reaction or combination between the sulfur dioxidand oxygen of the endothermic oxidizing agent when the gauze issubjected to the action of an electric current.

This coating permanently remains thereafter, isolating the metal partsfrom the gases and preventing contact therewith during its furtheremployment.

Having now described my invention, what 1 claim as new, and desire tosecure by Letters Patent, is

1. The process of making sulfur trioxid which consists in inducing theoxidation of sulfur dioxid with a gaseous oxidizing substance capable ofproducing an endothermic reaction, by supplying heat thereto, andkeeping the temperature from rising to the dissociating-point of sulfurtrioxid by controlling the heat supplied.

2. The process of making sulfur trioxid which consists in inducing anendothermic reaction between sulfur (lioxid and a gaseous oxidizingsubstance by the action of heat and maintaining the reactioncontinuously by conveying thereto a gaseous substance cont'ainin sulfurdioxid and oxidizing compound and preventing the temperature from risingto the dissociating-point of sulfur trioxid by controlling the heatsupplied.

3. The process of making sulfur trioxid which consists in supplying to agaseous mixture containing sulfur dioxid and an oxidizing compoundenough heat to induce an endothermic reaction between the same andmaintaining the temperature below the dissociating-point of sulfurtrioxid by regulating the supply of heat thereto.

4. The process of making sulfur trioxid which consists in performing areaction between sulfur dioxid and a gaseous substance capable ofproducing an denothermic reaction by passing the said mixture through acompartment wherein suilicient heat is supplied to induce a reaction andmaintain the same below the dissociating-point of sulfur trioxid bycontrolling the heat supplied thereto.

5. The process of making sulfur trioxid by direct thermal action whichconsists in inducing an endothermic reaction between sulfur dioxid andagaseous oxidizing agent by supplying suflicient heat thereto andmaintaining the reaction by continuing the supply of the mixture ofgases and heat.

6. The process of making sulfur trioxid which consists in oxidizingsulfur dioxid by means of endothermic reaction with a gaseous oxidizingcompound induced and maintained by supplying suflicient heat thereto tonontralize the deficiency therein.

7. The process of making sulfur trioxid by direct thermal action whichconsists in supplying that quantity of heat to a mixture of sulfurdioxid and carbon dioxid which will induce a reaction between the samewithout elevating the temperature of the mixture to thedissociating-point of sulfur trioxid.

8. The continuous process of making sulfur trioxid by direct thermalaction, which fur dioxid and producing a substance capable of absorbingheat during its formation, and abstracting the heat evolved during theoxidation of the sulfur content by the action of the substance absorbingheat-during its formation, whereby the temperature is prevented fromrising to the dissociating-point of sulfur trioxid.

10. The process of makinga compound consisting of one atom of sulfur andthree atoms of oxygen which consists in uniting substances forming thesame and simultaneously producing a substance capable of absorbing heatduring its formation, and apportioning anddisposing the ingredients sothat the heat which would result in the formation of one is absorbed bythe other to such a degree that the generation of a temperaturesuflicient to dissociate sulfur trioxid is avoided.

- 11. The process of making compounds containing sulfur which evolveheat on their formation which consists in uniting substances forming thesame and simultaneously producing a substance capable. of absorbing heatduring its formation, and apportioning and disposing the ingredients sothat the heat which would be evolved in the formation of one is absorbedby the other to such a degree that the generation of a temperaturesufficient to dissociate the sulfur compound desired is avoided.

12. The process of making compounds containing sulfur which evolve heaton their formation which consists in uniting gaseous substances formingthe same, and simultaneously producing a substance capable of absorbingheat during its formation, and apportioning and disposing theingredients so that the heat which would be evolved in the formation ofone is absorbed by'the other to such a degree that the generation of atemperature sufficient to dissociate the sulfur-containing compound 1savolded.

18. The process of making compounds of sulfur and oxygen which evolveheat on their formation which consists in uniting substances forming thesame, and simultaneously producing a substance capable of absorbing heatduring its formation, and apportioning and disposing the ingredients sothat the heat which would be evolved in the formation of one is absorbedby the other, to such a degreethat the generation of a temperaturesufficient to dissociate the sulfur-oxygen compound is avoided.

14. The process of making compounds of sulfur and oxygen which evolveheat on their formation which consists in uniting gaseous substancesforming the same and simultaneously producing a substance capable ofabsorbing heat during its formation, and apportioning and disposing theingredients so that the heat which would result in the formation of oneis absorbed by the other to such a degree that the generation of atemperature sufficient to dissociate the sulfur-oxygen compound isavoided.

15. The process of making compounds which evolve heat during theirformation which con: sists in uniting substances forming the same andsimultaneously producing a substance which will absorb heat during itsformation, and apportioning and disposing the ingredients so that theheat which would be evolved by one is absorbed in the formation of theother to such a degree that a temperature sufficient to dissociate thecompound desired is avoided.

gree that a temperature suflicient to dissociatethe substance desired isavoided and finally causing the said ingredients to reactsimultaneously.

17. The process of making substances which are unstable at elevatedtemperatures and which evolve heat on their formation which 1 consistsin exposing thesaid substance during its formation to the action ofchemical refrigeration.

18. The process of making compounds containing sulfur which evolve heatduring their formation which consists in exposing the saidsulfur-containing substance during its forma tion to the action ofchemical refrigeration.

19. The process of making compounds of sulfur and oxygen which consistsin oxidizing sulfur while subjecting it to chemical refrigeration.

20. The process of making sulfur trioxid which consists in oxidizingsulfur dioxid while subjecting it to chemical refrigeration.

In testimony whereof I aflix my signature in presence of two witnesses.

HENRY SPENCER BLAOKMORE.

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